posted by Anonymous on .
Calculate the concentration of NH4+ from ammonium chloride required to prevent the precipitation of Ca(OH)2 in a liter of solution that contains .10 mol of ammonia ans .10 mol pf calcium ion.
I got the two equations but I do not know where to begin.
The question asks for (NH4^+) yet you give an answer in Ca ion which doesn't make sense. Could you have meant that the solution contains 0.1 mol Ca ion?
yes .1 M Ca ion and .1 M ammonia
Ksp Ca(OH)2 = (Ca^+2)(OH^-)^2 =??
Kb = (NH4^+)(OH^-)/(NH3) =??
From equation 1, calculate (OH^-) needed for pptn with 0.1 M Ca ion.
From equation 2, using 0.1 M for (NH3), and the (OH^-) from equation 1, calculate (NH4^+).
Post your work if you get stuck.